Boaters watch cliff collapse along Lake Superior in Michigan
A cliff wall broke away at a national park along Lake Superior in northern Michigan, stunning some boaters who captured it on video. The park's cliffs are 50 feet to 200 feet (15.2 meters to 60.9 meters) above the lake. “We could hear the cliff wall popping and cracking and within 60 seconds a section of cliff approximately 200 feet wide fell before us," Jahn Martin told WLUC-TV.
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